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Graduation Thesis: MSc. Hydraulic Engineering (HSFR) Performance-Based Seismic Analysis of an Anchored Sheet Pile Quay Wall Date: July 2nd, 2015 Author: Student number: Camille Habets 1539558 Graduation Committee: Prof. Dr. Ir. S.N. Jonkman (Chairman Committee, Delft University of Technology, Section Hydraulic Engineering) Dr. Ir. J.G. de Gijt (Delft University of Technology, Section Hydraulic Engineering) Prof. Dr. A.V. Metrikine (Delft University of Technology, Sections Structural Mechanics and Offshore Engineering) Ir. D.J. Peters (Royal HaskoningDHV) 0

Preface Dear reader, In front of you is the result of the final project to complete my MSc. degree in Hydraulic Engineering at Delft University of Technology. I have worked on a topic which I think comprises significant theoretical consideration on the one hand and actual relevance for engineering practice on the other hand. Royal HaskoningDHV offered me the opportunity to work on this topic by means of a graduation internship at their Maritime & Waterways department in Rotterdam. For this opportunity I would like to thank Dennis Broere and Bunno Arends. Other people within the company who I would like to thank especially are John Adrichem for his active involvement and guidance in the seismic and geotechnical part, Jesper van Es for helping me with troubleshooting and understanding PLAXIS, Martin de Kant for more valuable advice on geotechnical content and Albert Wiggers for his participation in defining the scope of my work and his feedback. Last but not least I would like to thank Dirk Jan Peters for his role as one of my committee members on behalf of RHDHV and the inspiring guidance he has provided. And by that I come to thanking the other members of my graduation committee for their supervision and feedback: Bas Jonkman, Andrei Metrikine and Jarit de Gijt. Closing off I definitely want to thank Iris for listening to my continuous contemplations about the content of my graduation thesis and my parents, Werner and Wietske, for their full support during my study time. Camille Habets nd Delft, July 2 2015 i

Abstract Ports are civil works which have a major societal and economic importance. Quay structures are infrastructural elements of primary significance for the functioning of a port system. The ability to economically design quay structures with sufficient seismic resistance is therefore of great importance when situated in areas that are prone to earthquakes. Conventional seismic design is force-based i.e. that structures are designed to have sufficient capacity to withstand a pseudo-static seismic design force. This methodology is associated with no insight in the performance of the structure when exceeding the pseudo-static limit equilibrium state and uneconomic design due to the demand that the structure can resist a very high seismic design force without deforming. A more advanced alternative is Performance-Based Design (PBD) methodology. In this methodology the key design parameters for the seismic performance of structures are stress states and deformations of soil and structure, rather than just a seismic design force. Furthermore it recognizes that varying amounts of permanent deformations associated with different degrees of (repairable) damage are allowable. The present study is embedded in the topic of performance-based seismic design of quay structures. Typical quay types are gravity-based quay walls, sheet pile quay walls and pile-deck structures. The observed trend in seismic quay design is that gravity and sheet pile type structures (i.e. retaining walls) are associated with areas with zero to low seismicity while pile-deck structures are generally the preferred solution in areas with higher seismicity. This can be explained by more favourable seismic performance (i.e. more deformation capacity) of pile-deck structures compared to retaining walls. In line with this trend it is found that PBD methodology is developed to significant lesser extent for retaining walls (especially anchored sheet pile walls) than for piledeck structures. Therefore the present study focuses on performance-based seismic design of anchored sheet pile quay walls. In the seismic design methodology there are generally three levels of seismic analysis available, i.e. simplified analysis (pseudo-static), simplified dynamic analysis and dynamic analysis. Simplified analysis of anchored sheet pile quay walls is associated with conventional design methodology. Simplified dynamic analysis can be used to obtain a first estimate of permanent-displacement of a structure after exceeding limit equilibrium, based on an assumed failure mode. This type of analysis has to be made more suitable for anchored sheet pile quay walls. In dynamic analysis the seismic behaviour of a structure can be simulated by means of finite element software. Experience has shown that it is desirable to consider sheet pile quay walls in a less conservative way in (preliminary) seismic design for which pseudo-static methodology is commonly applied. Therefore the general objective of the present study is to propose improvements on (simplified) seismic design methodologies for anchored sheet pile quay walls by considering deformation behaviour. For this purpose a research methodology is developed in which pseudo-static, permanent-displacement and FE analysis are employed, calibrated with an experimental reference case that considers a typical anchored sheet pile quay wall. The reference case is taken from a conference paper. It reports on a shake table test under centrifugal gravity which is performed on a scale model of an existing sheet pile quay wall with a batter pile anchor. The quay is situated in homogeneous soil that consists of coarse densified sand. Due to the soil condition liquefaction effects are prevented. Sequential seismic loading of increasing severity is applied during the shake table testing. Measurement results that are reported in the reference case paper comprise bending moments in the sheet pile wall, normal forces in the anchor rod and horizontal displacements of the sheet pile wall. For simplified analysis a calibrated D-SHEET PILING model of the reference case anchored sheet pile quay wall is created. Through an iterative pseudo-static calculation procedure in which D-SHEET PILING and reference case dynamic bending moment results are fitted, it is attempted to find a deformation-based seismic load reduction for structural forces in the sheet pile wall that can be applied in pseudo-static design methodology. ii

For simplified dynamic analysis an analytical limit equilibrium model is developed, based on the failure behaviour of the reference case. The goal of this model is that it can compute the critical acceleration of the anchored quay structure and estimate the sheet pile forces at this critical state. These abilities are validated with PLAXIS 2D and checked with the reference case measurements respectively. Six accelerograms in the reference case soil column, obtained with equivalent linear site-response analysis (with SHAKE2000), are combined with the computed critical acceleration for permanent-displacement (sliding-block) analysis. For dynamic analysis a calibrated PLAXIS 2D model of the reference case anchored sheet pile quay wall is created. Dynamic performance of the PLAXIS 2D model is validated with SHAKE2000 by comparing siteresponse analysis results of both models. Pseudo-static and pseudo-dynamic calculations are applied to obtain the critical acceleration. Dynamic calculations with six bedrock motions are carried out to simulate the reference case experiment. PLAXIS 2D calculation results are used to validate simplified and simplified dynamic analysis results and to gain insight in the seismic failure behaviour of the anchored sheet pile quay wall. Approaches for (simplified) performance-based seismic analysis of a typical anchored sheet pile quay wall are proposed as a result of the research. For pseudo-static methodology a deformation-based seismic load reduction for structural forces in the sheet pile wall is proposed. For the present reference case it is concluded that a reduction in the range of 45% to 50% is allowable. For simplified dynamic analysis a limit equilibrium model is proposed to compute the critical acceleration of the present quay structure and to estimate sheet pile forces at this critical state. It is concluded that the ability of the limit equilibrium model is satisfactory. Although subjected to uncertainty, permanent-displacement analysis results indicate that the sliding-block analysis, originally developed for embankments, is possibly not suitable for anchored sheet pile quay walls. For dynamic analysis it is concluded that PLAXIS 2D is able to compute the reference case failure behaviour reasonably well, despite some computational setbacks. Complementary is the conclusion that PLAXIS 2D pseudo-static approach proves to be suitable to determine the critical acceleration of an anchored sheet pile structure in contrast to pseudo-dynamic approach which appears less suitable for that matter. In addition the performance-based design principle is linked to the present study so that an idea about the seismic performance limits of anchored sheet pile quay walls in quantitative terms can be provided. As a result of the present study findings it is recommended to perform more extensive research on the ability of permanent-displacement analysis to evaluate the amount of sliding displacement of an anchored sheet pile quay wall. In line with this recommendation it is found that further research on site-response analysis is desirable in the application of simplified dynamic and dynamic analysis. In general it is recommended to create more seismic test cases with different setups for a broader validity of the present results, to develop a seismic test case for the Groningen earthquake situation, to add measurement instrumentation to new and existing structures for verification of research results and to make such (raw) measurement data available to the public. iii

Nomenclature Abbreviations ASCE CLE DA DL DSHA EERI EPRI FDM FEM FFT HTVB JFESP JMA K-NET KIK-NET KNMI MDE MLIT M-O MSK MMI NIED NCHRP NGA NSSMC OCDI OLE PA PARI PBD PEER PIANC POLB PSHA RHDHV SA SDA SDOF SSI TNO USACE USGS American Society of Civil Engineers Contingency Level Earthquake Dynamic Analysis Reference sea level Deterministic Seismic Hazard Analysis Earthquake Engineering Research Institute Electric Power Research Institute Finite Difference Method Finite Element Method Fast Fourier Transformation Hiap Teck Venture Berhad JFE Steel Corporation Japanese Meteorological Agency Kyoshin Network Kiban Kyoshin Network Koninklijk Nederlands Meteorologisch Instituut Maximum Design Earthquake Japanese Ministry of Land, Infrastructure, Transport and Tourism Mononobe-Okabe Medvedev-Spoonheuer-Karnik Modified Mercalli Intensity National Research Institute for Earth Science and Disaster Prevention National Cooperative Highway Research Program New Generation Attenuation database Nippon Steel & Sumitomo Metal Corporation Overseas Coastal Area Development Institute of Japan Operating Level Earthquake Pushover Analysis Port and Airport Research Institute, Japan Performance-Based Design Pacific Earthquake Engineering Research Center International Navigation Association Port Of Long Beach Probabilistic Seismic Hazard Analysis Royal HaskoningDHV Simplified Analysis Simplified Dynamic (or Displacement-based) Analysis Single Degree Of Freedom Soil-Structure Interaction Nederlandse Organisatie voor Toegepast-Natuurwetenschappelijk Onderzoek United States Army Corps of Engineers United States Geological Survey iv

Symbols 2 A ac ah or v amax Bm b C C1, 2 c D50 Dn Dwall deq E cross-sectional area of structural element [m ] 2 critical (or yield) acceleration [m/s ] 2 (design) ground acceleration in horizontal or vertical direction [m/s ] 2 maximum acceleration [m/s ] width of reference case field (or scale) model [m] (or [mm]) acting width of the beam (sheet pile) in D-SHEET PILING [m] damping matrix of the soil-structure system relaxation coefficients in PLAXIS 2D viscous boundary formulations [-] 2 cohesion of the soil material [kN/m ] soil material mid-particle diameter [mm] Newmark permanent displacement [m] embedment depth of sheet pile quay wall [m] equivalent thickness of plate element in PLAXIS 2D [m] 2 Young’s modulus of the soil or structure material [kN/m ] Eref 50 Eref oed Eref ur ED ES EA EI F Fanchor Fh or v Fmax,comp Fmax,tens Fm Fp G G0 Gmax Gs f f0 f1 f2 fp secant soil stiffness in standard drained triaxial test [kN/m ] 2 tangent soil stiffness for primary oedometer loading [kN/m ] 2 unloading-reloading soil stiffness [kN/m ] 2 2 dissipated energy in the soil during one hysteretic load cycle [kg.m /s ] 2 2 stored energy at maximum shear strain in the soil [kg.m /s ] axial stiffness of the structural element [kN/m] 2 bending stiffness of the structural element [kNm /m] force vector of the soil-structure system force in the anchor tie rod [kN] pseudo-static seismic force in horizontal or vertical direction [kN] Maximum compressive force in an anchor tie rod [kN] Maximum tensile normal force in an anchor tie rod [kN] dynamic moment factor [-] dynamic thrust factor [-] 2 shear modulus of the soil material [kN/m ] 2 initial or very small-strain shear modulus of the soil material [kN/m ] 2 maximum shear modulus of the soil material [kN/m ] 2 secant shear modulus of the soil material [kN/m ] frequency [Hz] natural frequency [Hz] Rayleigh damping target frequency 1 [Hz] Rayleigh damping target frequency 2 [Hz] total pressure on the beam (sheet pile) per running meter, including the reaction of the soil springs in D-SHEET PILING [kN/m] 2 gravitational acceleration [m/s ] out plane force in structural element [kN] height of reference case field (or scale) model [m] (or [mm]) height of soil deposit [m] total height of sheet pile quay wall [m] retaining height of sheet pile quay wall [m] height of sheet pile profile [mm] height schematized anchor pile in limit-equilibrium model [m] height of the water table with respect to toe of anchor pile in limit-equilibrium model [m] height of the vertical failure plane of the limit-equilibrium model [m] g H Hm Hsoil Htot Hwall h ha ha,w hT 2 v

hw h1 I Ia K KA(E) KP(E) K0 k k1, 2, 3 kcr kh kv ks La Lm Lplate l M M(max) MP m mb ML MS MW N N’ NP Nsf Pr;max;point pa pp pref PA(E) PP(E) pw Pw PGA PGV PGD q qc Q Rf RD r ru water depth in front of the sheet pile wall [m] vertical height of the failure plane beneath the sliding mass of the limit-equilibrium model [m] 4 moment of inertia of the structural element [m ] Arias Intensity [m/s] stiffness matrix of the soil-structure system (dynamic) active soil pressure coefficient [-] (dynamic) passive soil pressure coefficient [-] neutral soil pressure coefficient [-] soil material permeability [m/s] 3 moduli of subgrade reaction [kN/m ] critical (or yield) seismic coefficient [-] horizontal seismic coefficient [-] vertical seismic coefficient [-] shear correction factor in PLAXIS 2D structural calculations [-] length of anchor tie rod [m] length of reference case field (or scale) model [m] (or [mm]) length of plate element in PLAXIS 2D [m] anchor spacing [m] mass matrix of the soil-structure system (maximum) bending moment in the sheet pile quay wall [kNm] maximum plastic bending moment of a structural element [kNm] power for defining the amount of stress-level dependency of the soil stiffness moduli [-] body wave magnitude [-] Richter local magnitude [-] surface wave magnitude [-] moment magnitude [-] normal force in structural element or normal force in the failure plane beneath the sliding mass of the limit-equilibrium model [kN] effective component of the normal force in the failure plane beneath the sliding mass of the limit-equilibrium model [kN] maximum plastic normal force of a structural element [kN] scale factor in reference case [-] maximum point resistance [MPa] 2 active soil pressure on the retaining wall [kN/m ] 2 passive soil pressure on the retaining wall [kN/m ] reference soil stress [kPa] (dynamic) active soil thrust on the retaining wall [kN] (dynamic) passive soil thrust on the retaining wall [kN] 2 water pressure [kN/m ] water thrust on the wall [kN] 2 peak ground acceleration [m/s ] 2 peak ground velocity [m/s ] peak ground displacement [m] ductility factor [-] cone resistance [MPa] shear force in the structural element [kN] failure ratio in PLAXIS 2D HSsmall model [-] relative density [%] reduction factor on pseudo-static seismic load (deformation-based) [-] pore pressure ratio [-] vi

S Sa T T0 Tavg Tm TP Ts t U1 U2 U2,W U3 ü 𝐮̇ u̇ x u̇ y u u uanchor useabed W w Vp Vs Xi x z shear force along the failure plane beneath the sliding mass of the soil-structure system [kN] 2 spectral acceleration [m/s ] force in anchor tie rod [kN] smoothed predominant spectral period [s] average spectral period [s] mean period [s] predominant spectral period [s] site period [s] time [s] hydrostatic force in failure plane beneath the sliding mass of the limit-equilibrium model [kN] hydrostatic force in front of sheet pile quay wall in the limit-equilibrium model [kN] Westergaard hydrodynamic force over the water depth in front of sheet pile quay wall [kN] hydrostatic force behind the vertical failure plane of the limit-equilibrium model [kN] acceleration vector of the soil-structure system velocity vector of the soil-structure system seismic wave velocity in x-direction [m/s] seismic wave velocity in y-direction [m/s] displacement vector of the soil-structure system horizontal soil displacement [m] horizontal displacement of the sheet pile quay wall at anchor level [mm] horizontal displacement of the sheet pile quay wall at seabed level [mm] mass of the soil-structure system (including added mass) [kg] horizontal displacement of the beam (sheet pile) in D-SHEET PILING [m] compression wave velocity of the soil material [m/s] shear wave velocity of the soil material [m/s] factor in D-SHEET PILING depending on number of CPT’s and anchors in the model coordinate along the axis of the beam (sheet pile) in D-SHEET PILING [m] depth in soil column [m] αAE αN, βN αR βR β γav γb γdry γeq γsat γunsat γw ϒ ϒ* ϒ0.7 ϒc Δu x δ εN angle of the planar failure surface behind the retaining wall with respect to the horizontal [ ] Newmark numerical integration coefficients [-] Rayleigh damping coefficient associated with mass [-] Rayleigh damping coefficient associated with stiffness [-] inclination angle of the backfill with respect to the horizontal [ ] 3 average unit weight of soil [kN/m ] 3 buoyant unit weight of soil [kN/m ] 3 dry unit weight of the soil [kN/m ] 3 equivalent unit weight of soil [kN/m ] 3 saturated unit weight of the soil [kN/m ] 3 unsaturated unit weight of the soil [kN/m ] 3 unit weight water [kN/m ] shear strain [-] modified shear strain in PLAXIS 2D calculations for better numerical results [-] shear strain level at which Gs is reduced to 72.2% of G0 [-] maximum shear strain [-] 2 excess pore pressure [kN/m ] elongation [m] soil wall friction angle [ ] normal strain [-] vii

ε2 η θ θfp κ λ ν ξ ρ σ σ’ σN σ2 τ ϕ ϕcrit ϕmax φ ψ ψmax ω1, 2 out of plane strain [-] dynamic viscosity of the (soil) material [kg/m·s] inclination angle of the retaining wall interface with respect to the vertical [ ] angle of the failure plane beneath the sliding mass of the limit-equilibrium model, with respect to the horizontal [ ] curvature of a structural element [1/m] ratio between saturated height and total height of the retaining wall [-] Poisson’s ratio [-] (hysteretic) damping ratio [%] 3 volumetric mass density of (soil) material [kg/m ] 2 total soil stress [kN/m ] 2 effective soil stress [kN/m ] 2 normal stress [kN/m ] 2 out of plane stress [kN/m ] 2 shear stress [kN/m ] internal friction angle of the soil [ ] internal friction angle of the soil corresponding to shearing observed in a simple shear test on soil loose enough to be in a critical state, with zero dilatation [ ] internal friction angle of the soil corresponding to maximum soil strength [ ] diameter anchor tie rod [mm] inclination angle of the seismic coefficient k with the vertical [ ] dilation angle of the soil material [ ] Rayleigh damping angular frequencies [rad/s] viii

Contents Preface .i Abstract .ii Nomenclature . iv 1. 2. Introduction. 1 1.1. Topic description . 1 1.2. Contents . 1 General theoretical background. 2 2.1. 2.1.1. Earthquake sources. 2 2.1.2. Earthquake size . 4 2.1.3. Seismic waves . 4 2.2. Seismic hazards and port structures . 5 2.2.1. Ground shaking hazard . 6 2.2.2. Soil liquefaction hazard . 8 2.2.3. Tsunami hazard . 8 2.2.4. Quay wall structures and typical seismic failure modes . 9 2.3. Seismic design methodology . 11 2.3.1. Conventional seismic design . 11 2.3.2. Performance-based seismic design. 12 2.4. Site response analysis . 16 2.4.1. Local site effects . 16 2.4.2. Equivalent linear site-response analysis . 17 2.4.3. Nonlinear site-response analysis . 17 2.5. Seismic structural analysis . 18 2.5.1. Simplified analysis . 18 2.5.2. Simplified displacement-based analysis . 21 2.5.3. Dynamic analysis . 23 2.6. 3. Earthquakes . 2 Trends in seismic design of quay structures . 25 Research description . 26 3.1. Problem definition . 26 3.2. Research question . 27 3.3. Outline of the research methodology . 27 3.3.1. Step 1: Reference case selection . 28 3.3.2. Step 2: Simplified analysis . 28 3.3.3. Step 3: Simplified dynamic analysis . 29 ix

4. 5. 3.3.4. Step 4: Dynamic analysis . 30 3.3.5. Step 5: Evaluation of analysis results . 30 Reference case . 31 4.1. Reference case selection . 31 4.2. Reference case definition . 31 4.2.1. Model setup: geometry and parameters . 31 4.2.2. Testing procedure . 33 4.2.3. Test results . 35 Seismic analysis of the reference case . 37 5.1. 5.1.1. Introduction . 37 5.1.2. D-SHEET PILING model . 38 5.1.3. Static calibration of the D-Sheet Piling model with the reference case . 40 5.1.4. Pseudo-static calculations. 43 5.1.5. Results . 44 5.2. Simplified dynamic analysis: permanent-displacement . 49 5.2.1. Introduction . 49 5.2.2. Limit-equilibrium model: critical acceleration . 49 5.2.3. Limit equilibrium model: structural forces in the sheet pile wall . 52 5.2.4. SHAKE2000 model: site-response analysis . 53 5.2.5. SLAMMER model: permanent-displacement analysis . 57 5.2.6. Results . 60 5.3. 6. Simplified analysis: pseudo-static . 37 Dynamic analysis: finite element method . 62 5.3.1. Introduction . 62 5.3.2. PLAXIS 2D model . 62 5.3.3. Static calibration of the PLAXIS 2D model with the reference case. 65 5.3.4. Pseudo-static and pseudo-dynamic computation of the critical acceleration . 66 5.3.5. Dynamic calibration of the PLAXIS 2D model: site-response analysis . 69 5.3.6. Calibrated dynamic calculations with the PLAXIS 2D model . 74 Evaluation . 82 6.1. Reference case.

quay types are gravity-based quay walls, sheet pile quay walls and pile-deck structures. The observed trend in seismic quay design is that gravity and sheet pile type structures (i.e. retaining walls) are associated with areas with zero to low seismicity while pile-deck structures are generally the preferred solution in areas with higher .

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